[S390] virtualization aware cpu measurement

Use the SPP instruction to set a tag on entry to / exit of the virtual
machine context. This allows the cpu measurement facility to distinguish
the samples from the host and the different guests.

Signed-off-by: Carsten Otte <cotte@de.ibm.com>

4 files changed, 24 insertions, 11 deletions

diff --git a/arch/s390/kernel/asm-offsets.c b/arch/s390/kernel/asm-offsets.c
index 816d81f479c0..44a4336d9a33 100644
--- a/arch/s390/kernel/asm-offsets.c
+++ b/arch/s390/kernel/asm-offsets.c
@@ -131,6 +131,8 @@ int main(void)
         DEFINE(__LC_MCCK_CLOCK, offsetof(struct _lowcore, mcck_clock));
         DEFINE(__LC_MACHINE_FLAGS, offsetof(struct _lowcore, machine_flags));
         DEFINE(__LC_FTRACE_FUNC, offsetof(struct _lowcore, ftrace_func));
+        DEFINE(__LC_SIE_HOOK, offsetof(struct _lowcore, sie_hook));
+        DEFINE(__LC_CMF_HPP, offsetof(struct _lowcore, cmf_hpp));
         DEFINE(__LC_IRB, offsetof(struct _lowcore, irb));
         DEFINE(__LC_CPU_TIMER_SAVE_AREA, offsetof(struct _lowcore, cpu_timer_save_area));
         DEFINE(__LC_CLOCK_COMP_SAVE_AREA, offsetof(struct _lowcore, clock_comp_save_area));
diff --git a/arch/s390/kernel/early.c b/arch/s390/kernel/early.c
index 2d92c2cf92d7..c00856ad4e5a 100644
--- a/arch/s390/kernel/early.c
+++ b/arch/s390/kernel/early.c
@@ -356,6 +356,7 @@ static __init void detect_machine_facilities(void)
 {
 #ifdef CONFIG_64BIT
         unsigned int facilities;
+        unsigned long long facility_bits;
 
         facilities = stfl();
         if (facilities & (1 << 28))
@@ -364,6 +365,9 @@ static __init void detect_machine_facilities(void)
                 S390_lowcore.machine_flags |= MACHINE_FLAG_PFMF;
         if (facilities & (1 << 4))
                 S390_lowcore.machine_flags |= MACHINE_FLAG_MVCOS;
+        if ((stfle(&facility_bits, 1) > 0) &&
+            (facility_bits & (1ULL << (63 - 40))))
+                S390_lowcore.machine_flags |= MACHINE_FLAG_SPP;
 #endif
 }
 
diff --git a/arch/s390/kernel/entry64.S b/arch/s390/kernel/entry64.S
index 6536f5ca46f5..829b759ba1e1 100644
--- a/arch/s390/kernel/entry64.S
+++ b/arch/s390/kernel/entry64.S
@@ -2,7 +2,7 @@
  *  arch/s390/kernel/entry64.S
  *    S390 low-level entry points.
  *
- *    Copyright (C) IBM Corp. 1999,2006
+ *    Copyright (C) IBM Corp. 1999,2010
  *    Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
  *               Hartmut Penner (hp@de.ibm.com),
  *               Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com),
@@ -59,6 +59,16 @@ _TIF_SYSCALL = (_TIF_SYSCALL_TRACE>>8 | _TIF_SYSCALL_AUDIT>>8 | \
 
 #define BASED(name) name-system_call(%r13)
 
+        .macro  HANDLE_SIE_INTERCEPT
+#if defined(CONFIG_KVM) || defined(CONFIG_KVM_MODULE)
+        lg      %r3,__LC_SIE_HOOK
+        ltgr    %r3,%r3
+        jz      0f
+        basr    %r14,%r3
+        0:
+#endif
+        .endm
+
 #ifdef CONFIG_TRACE_IRQFLAGS
         .macro  TRACE_IRQS_ON
         basr    %r2,%r0
@@ -466,6 +476,7 @@ pgm_check_handler:
         UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
         mvc     __LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
 pgm_no_vtime:
+        HANDLE_SIE_INTERCEPT
         TRACE_IRQS_CHECK_OFF
         lg      %r9,__LC_THREAD_INFO    # load pointer to thread_info struct
         mvc     SP_ARGS(8,%r15),__LC_LAST_BREAK
@@ -507,6 +518,7 @@ pgm_per_std:
         UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
         mvc     __LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
 pgm_no_vtime2:
+        HANDLE_SIE_INTERCEPT
         TRACE_IRQS_CHECK_OFF
         lg      %r9,__LC_THREAD_INFO    # load pointer to thread_info struct
         lg      %r1,__TI_task(%r9)
@@ -570,6 +582,7 @@ io_int_handler:
         mvc     __LC_LAST_UPDATE_TIMER(8),__LC_ASYNC_ENTER_TIMER
 io_no_vtime:
         lg      %r9,__LC_THREAD_INFO    # load pointer to thread_info struct
+        HANDLE_SIE_INTERCEPT
         TRACE_IRQS_OFF
         la      %r2,SP_PTREGS(%r15)     # address of register-save area
         brasl   %r14,do_IRQ             # call standard irq handler
@@ -595,15 +608,6 @@ io_done:
 io_work:
         tm      SP_PSW+1(%r15),0x01     # returning to user ?
         jo      io_work_user            # yes -> do resched & signal
-#if defined(CONFIG_KVM) || defined(CONFIG_KVM_MODULE)
-        lg      %r2,SP_PSW+8(%r15)      # check if current instruction is SIE
-        lh      %r1,0(%r2)
-        chi     %r1,-19948              # signed 16 bit compare with 0xb214
-        jne     0f                      # no -> leave PSW alone
-        aghi    %r2,4                   # yes-> add 4 bytes to leave SIE
-        stg     %r2,SP_PSW+8(%r15)
-0:
-#endif
 #ifdef CONFIG_PREEMPT
         # check for preemptive scheduling
         icm     %r0,15,__TI_precount(%r9)
@@ -712,6 +716,7 @@ ext_int_handler:
         mvc     __LC_LAST_UPDATE_TIMER(8),__LC_ASYNC_ENTER_TIMER
 ext_no_vtime:
         lg      %r9,__LC_THREAD_INFO    # load pointer to thread_info struct
+        HANDLE_SIE_INTERCEPT
         TRACE_IRQS_OFF
         la      %r2,SP_PTREGS(%r15)     # address of register-save area
         llgh    %r3,__LC_EXT_INT_CODE   # get interruption code
@@ -786,6 +791,7 @@ mcck_no_vtime:
         stosm   __SF_EMPTY(%r15),0x04   # turn dat on
         tm      __TI_flags+7(%r9),_TIF_MCCK_PENDING
         jno     mcck_return
+        HANDLE_SIE_INTERCEPT
         TRACE_IRQS_OFF
         brasl   %r14,s390_handle_mcck
         TRACE_IRQS_ON
diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c
index 598752499c3e..7d893248d265 100644
--- a/arch/s390/kernel/setup.c
+++ b/arch/s390/kernel/setup.c
@@ -2,7 +2,7 @@
  *  arch/s390/kernel/setup.c
  *
  *  S390 version
- *    Copyright (C) 1999,2000 IBM Deutschland Entwicklung GmbH, IBM Corporation
+ *    Copyright (C) IBM Corp. 1999,2010
  *    Author(s): Hartmut Penner (hp@de.ibm.com),
  *               Martin Schwidefsky (schwidefsky@de.ibm.com)
  *
@@ -401,6 +401,7 @@ setup_lowcore(void)
         lc->io_new_psw.mask = psw_kernel_bits;
         lc->io_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) io_int_handler;
         lc->clock_comparator = -1ULL;
+        lc->cmf_hpp = -1ULL;
         lc->kernel_stack = ((unsigned long) &init_thread_union) + THREAD_SIZE;
         lc->async_stack = (unsigned long)
                 __alloc_bootmem(ASYNC_SIZE, ASYNC_SIZE, 0) + ASYNC_SIZE;